NEW FEATURES

•  Reduced in Size : 300 Wide X 625 High X 810 Long including Spigots
• EC fans as standard
• No combustible materials used in construction
• Sheet metal painted construction
• High temperature sensor shuts down make-up air  runs exhaust fan to full speed
• High efficiency exchanger to 94%
• Greater than 82% when dry
• Microprocessor controller
• Optional IR remote control
• Optional summer bypass damper

Safe for you and your family:

• Not a system that can grow mould or organisms
• A system that can be cleaned and disinfected
• Non-combustible – no materials that support combustion or introduce toxins to your family – styrene vapour is toxic
• Smoke extract – a must have ! ! !
• Easy to clean (periodically) & change filters
• Easy to Operate

Normal Operation:

• The supply and extract air temperatures, Tin and Tout are monitored
• On start-up, if the difference between Tin and Tout is outside a (programmable) control band, the supply fan is throttled back until the control band narrows
• Strategy is set to avoid cold air feeds – the extract fan is unaffected
• The unit is fitted with a set of remote on/off contacts that can be wired back to a switch, motion sensor or timeclock as convenient.
• A set of contacts is also provided for extract fan boost, in the event of a contact closure from a humidity sensor or other contact closure.
  

Protection of occupants:

• If the extract temperature, Tout reaches a pre-determined high temperature (say 30 degrees), the system assumes a fire, over-rides any set-points and sets the extract fan to full fan speed  to maximise smoke removal
• The supply make up fan is also shut down to prevent feeding fresh air to the fire
• A set of fire alarm contacts is also provided that can be used to activate the same procedure as outlined above

Heat Exchangers are normally sized in Cubic Meters/Hour (M3/hr)

Minimum ventilation from Building Regulations based on the area of the house and accupancy - minimum is 0.3 Liters /sec /M2 of floor area for a family of 4 + 4 Liters /sec for every additional occupant
Assume a house of 100M2, multiply 0.3 = 30 liters / second, which, is very small at less than 10 M3/hr
BER is based on between one quarter and one third of an air change per Hour, which for 100M2 at 2.6M high is 90 M3/Hour.

Rules of thumb:

• 100M2 (1000 Sq Ft)    ~ 90M3 /Hour
• 150M2 (1500 Sq Ft)    ~ 130M3 /Hour
• 200M2 (2000 Sq Ft)    ~ 180M3 /Hour
• 300M2 (3000 Sq Ft)    ~ 260M3 /Hour
• 400M2 (4000 Sq Ft)    ~ 350M3 /Hour

Running Costs:

Assumptions

• 200M3/hr of air moved - based on 1/3 air change, this equates to 230M2 house (2,300 Sq Ft)
• Indoor temperature in house is 24oC
• Average outdoor air temperature in Ireland is 12 degrees C
• Temperature difference averages 12oC for 24/7/365 

Uncontrolled infiltration

• Cost is 0.81kW to heat 200M3 up 12oC
• Cost per kW from ESB (May ’09) is 14.55 + VAT @ 13.5% = 16.51 cent / kWhr
• Annual cost for uncontroller infiltration is:    € 1,033
  

Dedicated Mechanical Ventilation

• Operating at, say 85% on average with dry efficiency of 82% and wet of 92%
• Assume 15% losses in ventilation, lost heat is € 155 to recover
• Based on  say, 0.7W/l/s. which is equivalent to 75W, then annual running cost = € 108 pa.

Operating savings

• Based on 24/7/365 or 8,766 hours per year = € 1,033 - € 155 - € 108 = € 770
• For a 12oC temperature difference:        € 770 pa
• For a 10oC temperature difference:        € 640 pa